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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">cheb</journal-id><journal-title-group><journal-title xml:lang="ru">Чебышевский сборник</journal-title><trans-title-group xml:lang="en"><trans-title>Chebyshevskii Sbornik</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2226-8383</issn><publisher><publisher-name>Tula State Lev Tolstoy  Pedagogical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.22405/2226-8383-2025-26-5-287-298</article-id><article-id custom-type="elpub" pub-id-type="custom">cheb-2135</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Краткие сообщения</subject></subj-group></article-categories><title-group><article-title>Теорема единственности для бигармонических функций, заданных в трехмерном евклидовом пространстве 𝑅3</article-title><trans-title-group xml:lang="en"><trans-title>Uniqueness theorem for biharmonic functions given in three-dimensional Euclidian space 𝑅3</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ашурова</surname><given-names>Зебинисо Рахимовна</given-names></name><name name-style="western" xml:lang="en"><surname>Ashurova</surname><given-names>Zebiniso Rahimovna</given-names></name></name-alternatives><bio xml:lang="ru"><p>доцент</p></bio><bio xml:lang="en"><p>associate professor</p></bio><email xlink:type="simple">zeb1957niso@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Жураева</surname><given-names>Умидахон Юнусалиевна</given-names></name><name name-style="western" xml:lang="en"><surname>Jurayeva</surname><given-names>Umidakhon Yunusalievna</given-names></name></name-alternatives><bio xml:lang="ru"><p>докторант</p></bio><bio xml:lang="en"><p>doctoral student</p></bio><email xlink:type="simple">umida_9202@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Жураева</surname><given-names>Нодирахон Юнусовна</given-names></name><name name-style="western" xml:lang="en"><surname>Jurayeva</surname><given-names>Nodirakhon Yunusovna</given-names></name></name-alternatives><bio xml:lang="ru"><p>доцент</p></bio><bio xml:lang="en"><p>associate professor</p></bio><email xlink:type="simple">nodira8181@mail.ru</email><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Маллаева</surname><given-names>Феруза Уткиржановна</given-names></name><name name-style="western" xml:lang="en"><surname>Mallaeva</surname><given-names>Feruza Utkirjanovna</given-names></name></name-alternatives><bio xml:lang="ru"><p>студент</p></bio><bio xml:lang="en"><p>student,</p></bio><email xlink:type="simple">feruzamallayeva2405@gmail.com</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Узбекско-Финляндский педагогический институт</institution><country>Узбекистан</country></aff><aff xml:lang="en"><institution>Uzbek-Finnish Pedagogical Institute</institution><country>Uzbekistan</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Самаркандский государственный университет</institution><country>Узбекистан</country></aff><aff xml:lang="en"><institution>Samarkand State University</institution><country>Uzbekistan</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Ташкентский университет информационных технологий имени Мухаммада ал-Хоразмий</institution><country>Узбекистан</country></aff><aff xml:lang="en"><institution>Tashkent University of Information Technologies named after Mu-hammad al-Kharazmi</institution><country>Uzbekistan</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2025</year></pub-date><pub-date pub-type="epub"><day>21</day><month>01</month><year>2026</year></pub-date><volume>26</volume><issue>5</issue><fpage>287</fpage><lpage>298</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Ашурова З.Р., Жураева У.Ю., Жураева Н.Ю., Маллаева Ф.У., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Ашурова З.Р., Жураева У.Ю., Жураева Н.Ю., Маллаева Ф.У.</copyright-holder><copyright-holder xml:lang="en">Ashurova Z.R., Jurayeva U.Y., Jurayeva N.Y., Mallaeva F.U.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.chebsbornik.ru/jour/article/view/2135">https://www.chebsbornik.ru/jour/article/view/2135</self-uri><abstract><p>Настоящая работа посвящена изучения свойств специальной построенной функции𝜙𝜎(𝑦, 𝑥), которая задана в бесконечной области D трехмерного евклидова пространства.В данной работе доказываются результаты, позволяющие утверждать ограниченность бигармонической функции внутри некоторой трехмерной области, если она ограничена со своей нормальной производной на границе этой области.</p></abstract><trans-abstract xml:lang="en"><p>This work is devoted to studying the properties of the method of the constructed function𝜙𝜎(𝑦, 𝑥), which is defined in the infinite domain D of three-dimensional Euclidean space. In thiswork, we prove results that allow us to assert the boundedness of a biharmonic function insidea certain three-dimensional region if it is bounded with its normal derivative at the boundariesof this region.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>гармонические функции</kwd><kwd>бигармонические функции</kwd><kwd>полигармонические функции</kwd><kwd>функция Карлемана</kwd><kwd>теорема единственности.</kwd></kwd-group><kwd-group xml:lang="en"><kwd>harmonic functions</kwd><kwd>biharmonic functions</kwd><kwd>polyharmonic functions</kwd><kwd>Carleman function</kwd><kwd>uniqueness theorem.</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Евграфов М.А., Чегис И.А., Обобшение теоремы типа Фрагмена-Линделефа для аналитических функций на гармонические функции в пространстве, // Доклады Академии наук СССP, 134, 252–262, 1960.</mixed-citation><mixed-citation xml:lang="en">Evgrafov, M.A. &amp; Chegis, I.A. 1960, “Generalization of the Phragm´en-Lindelof type theorem for analytic functions to harmonic functions in space”, Doklady Akademii Nauk SSSR, vol. 134, pp. 252–262.</mixed-citation></citation-alternatives></ref><ref id="cit2"><label>2</label><citation-alternatives><mixed-citation xml:lang="ru">Чегис И.А.,Теорема типа Фрагмена-Линделефа для гармонических функций в прямоугольном цилиндре, //Доклады Академии наук СССP, 556–559, 1961.</mixed-citation><mixed-citation xml:lang="en">Chegis, I.A. 1961, “A Phragm´en-Lindelof type theorem for harmonic functions in a rectangular cylinder”, Doklady Akademii Nauk SSSR, vol. 141, pp. 556–559.</mixed-citation></citation-alternatives></ref><ref id="cit3"><label>3</label><citation-alternatives><mixed-citation xml:lang="ru">Аршон И.С., Евграфов М.А.,О росте функций, гармонических в цилиндре и ограниченных на его поверхности вместе с нормальной производной, //Доклады Академии наук СССP, 321–324, 1962.</mixed-citation><mixed-citation xml:lang="en">Arshon, I.S. &amp; Evgrafov, M.A. 1962, “On the growth of functions harmonic in a cylinder and bounded on its surface together with the normal derivative”, Doklady Akademii Nauk SSSR, vol. 147, pp. 321–324.</mixed-citation></citation-alternatives></ref><ref id="cit4"><label>4</label><citation-alternatives><mixed-citation xml:lang="ru">Аршон И.С., Евграфов М.А.,Пример гармонической во всем пространстве функции, // ограниченной вне круглого цилиндра, Доклады Академии наук СССP, 231–234, 1962.</mixed-citation><mixed-citation xml:lang="en">Arshon, I.S. &amp; Evgrafov, M.A. 1962, “Example of a harmonic function in the entire space bounded outside a circular cylinder”, Doklady Akademii Nauk SSSR, vol. 147, pp. 231–234.</mixed-citation></citation-alternatives></ref><ref id="cit5"><label>5</label><citation-alternatives><mixed-citation xml:lang="ru">Аршон И.С., Евграфов М.А., О росте гармонических функций трех переменных,// Доклады Академии наук СССP, 147, 347–351, 1962.</mixed-citation><mixed-citation xml:lang="en">Arshon, I.S. &amp; Evgrafov, M.A. 1962, “On the growth of harmonic functions of three variables”, Doklady Akademii Nauk SSSR, vol. 147, pp. 347–351.</mixed-citation></citation-alternatives></ref><ref id="cit6"><label>6</label><citation-alternatives><mixed-citation xml:lang="ru">Леоньтев А.Ф., О теоремах типа Фрагмена-Линделефа для гармонических функций в цилиндре, //Изв. АН СССР. Сер.матем, 661–676, 1963.</mixed-citation><mixed-citation xml:lang="en">Leontiev, A.F. 1963, “On Phragm´en-Lindelof type theorems for harmonic functions in a cylinder”, Izvestiya Akademii Nauk SSSR. Seriya Matematicheskaya, vol. 27, pp. 661–676.</mixed-citation></citation-alternatives></ref><ref id="cit7"><label>7</label><citation-alternatives><mixed-citation xml:lang="ru">Ярмухамедов Ш.Я., Задача Коши для полигармонического уравнения, //Доклады РАН, 162–165, 2003.</mixed-citation><mixed-citation xml:lang="en">Yarmukhamedov, Sh.Ya. 2003, “The Cauchy problem for the polyharmonic equation”, Doklady Rossiiskoi Akademii Nauk, vol. 393, no. 2, pp. 162–165.</mixed-citation></citation-alternatives></ref><ref id="cit8"><label>8</label><citation-alternatives><mixed-citation xml:lang="ru">Ашурова З.Р.,Жураева Н.Ю.,Жураева У.Ю., О некоторых свойствах ядро Ярмухамедова, //International Journal of Innovative Research, 84–90, 2021, Impact Factor 7.512.</mixed-citation><mixed-citation xml:lang="en">Ashurova, Z.R., Jurayeva, N.Yu. &amp; Jurayeva, U.Yu. 2021, “On some properties of the Yarmukhamedov kernel”, International Journal of Innovative Research, vol. 10, no. 1, pp. 84–90.</mixed-citation></citation-alternatives></ref><ref id="cit9"><label>9</label><citation-alternatives><mixed-citation xml:lang="ru">Ashurova Z.R., Jurayeva N.YU.,Jurayeva U.Yu., Growing Polyharmonic functions and Cauchy problem, //Journal of Critical Reviews, India, 7,371–378, 10.31938.jcr.07.06.62,2020.</mixed-citation><mixed-citation xml:lang="en">Ashurova, Z.R., Jurayeva, N.Yu. &amp; Jurayeva, U.Yu. 2020, “Growing polyharmonic functions and the Cauchy problem”, Journal of Critical Reviews, vol. 7, no. 6, pp. 371–378, doi: 10.31938/jcr.07.06.62.</mixed-citation></citation-alternatives></ref><ref id="cit10"><label>10</label><citation-alternatives><mixed-citation xml:lang="ru">Ashurova Z.R., Jurayeva N.YU.,Jurayeva U.Yu., Task Cauchy and Carleman function, Academicia: An International Multidisciplinary Research Journal, Affiliated to Kurukshetra University, // Kurukshetra India, 371–378, 2020, http://saarj.com.</mixed-citation><mixed-citation xml:lang="en">Ashurova, Z.R., Jurayeva, N.Yu. &amp; Jurayeva, U.Yu. 2020, “Task Cauchy and Carleman function”, Academicia: An International Multidisciplinary Research Journal, vol. 10, no. 6, pp. 371–378, [Online] Available at: http://saarj.com [Accessed 19 December 2024].</mixed-citation></citation-alternatives></ref><ref id="cit11"><label>11</label><citation-alternatives><mixed-citation xml:lang="ru">Голузин Г. М., Обобщенная формула Карлемана и ее приложение к аналитичecкому продолжению функций, //Математический сборник, 144–149, 1933.</mixed-citation><mixed-citation xml:lang="en">Goluzin, G.M. 1933, “The generalized Carleman formula and its application to analytic continuation of functions”, Matematicheskii Sbornik, vol. 40, no. 2, pp. 144–149.</mixed-citation></citation-alternatives></ref><ref id="cit12"><label>12</label><citation-alternatives><mixed-citation xml:lang="ru">Тихонов А. Н., Об устойчивости обратных задач, //ДАН СССР, 195–198, 1943.</mixed-citation><mixed-citation xml:lang="en">Tikhonov, A.N. 1943, “On the stability of inverse problems”, Doklady Akademii Nauk SSSR, vol. 39, no. 5, pp. 195–198.</mixed-citation></citation-alternatives></ref><ref id="cit13"><label>13</label><citation-alternatives><mixed-citation xml:lang="ru">Лаврентьев М.М.,Романов В.Г., Некорректные задачи математической физики и анализа,// Москва, Наука, 1990.</mixed-citation><mixed-citation xml:lang="en">Lavrentyev, M.M. &amp; Romanov, V.G. 1990, Ill-posed problems of mathematical physics and analysis, Nauka, Moscow.</mixed-citation></citation-alternatives></ref><ref id="cit14"><label>14</label><citation-alternatives><mixed-citation xml:lang="ru">Ярмухамедов Ш.Я., Формула Грина в бесконечной области и ее применение, //ДАН СССР, 697–700, 1985.</mixed-citation><mixed-citation xml:lang="en">Yarmukhamedov, Sh.Ya. 1985, “Green’s formula in an infinite domain and its application”, Doklady Akademii Nauk SSSR, vol. 284, no. 5, pp. 697–700.</mixed-citation></citation-alternatives></ref><ref id="cit15"><label>15</label><citation-alternatives><mixed-citation xml:lang="ru">Жураева Н.Ю.,Жураева У.Ю,Саидов У.М, Функция Карлемана для полигармонических функций для некоторых областей лежащих в m-мерном четном евклидовом пространстве, //Uzbek Mathematical Journal, 64–68, 2011.</mixed-citation><mixed-citation xml:lang="en">Juraeva, N.Yu., Jurayeva, U.Yu. &amp; Saidov, U.M. 2011, “The Carleman function for polyharmonic functions in some regions in m-dimensional even Euclidean space”, Uzbek Mathematical Journal, no. 3, pp. 64–68.</mixed-citation></citation-alternatives></ref><ref id="cit16"><label>16</label><citation-alternatives><mixed-citation xml:lang="ru">Жураева У.Ю, Теоремы типа Фрагмена–Линделефа для бигармонических функций, Изв. вузов. Матем., 2022, номер 10, 42–65. DOI: https://doi.org/10.26907/0021-3446-2022-10-42-65</mixed-citation><mixed-citation xml:lang="en">Juraeva, U.Yu. 2022, “Phragm´en-Lindelof type theorems for biharmonic functions”, Izvestiya Vysshikh Uchebnykh Zavedenii. Matematika, no. 10, pp. 42–65, doi: 10.26907/0021-3446-2022-10-42-65.</mixed-citation></citation-alternatives></ref><ref id="cit17"><label>17</label><citation-alternatives><mixed-citation xml:lang="ru">Жураева У.Ю, Теоремы типа Фрагмена–Линделефа, Дифференциальное уравнения, 2024, том 60, № 8, с. 1063–1075. DOI: 10.31857/S0374064124080059, EDN: KDBSIQ</mixed-citation><mixed-citation xml:lang="en">Juraeva, U.Yu. 2024, “Phragm´en-Lindelof type theorems”, Differential Equations, vol. 60, no. 8, pp. 1063–1075, doi: 10.31857/S0374064124080059.</mixed-citation></citation-alternatives></ref><ref id="cit18"><label>18</label><citation-alternatives><mixed-citation xml:lang="ru">Juraeva U.Yu., The Phragmen-Lindelof type theorems,Uzbek Mathematical Journal, 2022, Volume 66, Issue 3, pp.54-61. DOI: 10.29229/uzmj.2022-3-7.</mixed-citation><mixed-citation xml:lang="en">Juraeva, U.Yu. 2022, “The Phragmen-Lindelof type theorems”, Uzbek Mathematical Journal, vol. 66, no. 3, pp. 54–61, doi: 10.29229/uzmj.2022-3-7.</mixed-citation></citation-alternatives></ref></ref-list><fn-group><fn fn-type="conflict"><p>The authors declare that there are no conflicts of interest present.</p></fn></fn-group></back></article>
